A bus bar is a metal strip or bar that conducts electricity and is used for electrical power distribution. Battery cells can be connected with bus bars to make battery packs. Some battery packs using cylindrical cells make electrical connections to the tops and the bottoms of the cells. When connecting cells in series, bus bars and high current interconnects link the positive terminal of one cell, or a parallel group of cells, to the negative terminal of the next cell or the next parallel group of cells. However, connections to the bottoms of the cells obstruct airflow or liquid flow from cooling mechanisms utilized to remove heat generated by the cells. In addition, the high current interconnect from the bottoms of the cells to the bus bars, which may be in the form of a wire somewhat longer than the length of a cell, introduces a small amount of resistance which gives rise to a voltage drop at high current levels. Assembly of this wire to the bus bars or to the bottom of the battery adds costs to a battery pack and may introduce reliability issues.
It is within this context that the embodiments arise.